London: Personal rapid transit (PRT)

Personal rapid transit may be a the way of the future of urban transportation. (Source: ULTra Personal Rapid Transit System)

Most of us are familiar with forms of mass transport such as the bus, train and tram. They no longer exist in Australia, but some will also remember the trolleybuses that once rolled through the streets of some cities. Another one that is not common is the monorail, which has only ever been developed as serious mass transit in Japan, but for the most part it has just been used for tourist purposes.

One of the more recent forms of mass transit that is currently being trialled, but has not yet been implemented on a large scale in any city is personal rapid transit vehicles (or PRT). They involve the use of small automated vehicles (with no driver) running between two locations on a guideway network.

The key differences between this form of public transport and existing forms are that each vehicle carries a small number of people (usually 4-6 at most) and they can run to a requested location on the network on demand instead of running a fixed route with numerous stops. This minimises time wastage waiting for services to arrive and speeds up journey times.

On the guideway, the vehicles can detect each others presence and operate safely at 2-3 second headways. In this way, the system operates more gently than other forms of transport which are often stop-start and run several minutes apart rather than every few seconds.

In addition to the operational advantages, the PRT vehicles use rechargeable batteries which are charged up when vehicles are stopped at stations or other specified charge up points along the guideway. This provides the potential for various clean forms of energy to be used in providing the battery power for the vehicles.

At Heathrow Airport in London, this PRT system has been introduced on a small scale. A 4km long section of track has been built between the new Terminal 5 with its business carpark and if successful the system may be expanded to serve the rest of this giant airport and the surrounding communities. The following video shows how the system operates in London:

If the pilot project at Heathrow is successful, other cities may follow suit and introduce it to relieve congestion in cities where providing extra public transport in other forms has previously not been feasible. Some cities such as Guragon City in India and numerous cities in the US have already expressed their interest in building these systems.